| 摘要 |
PROBLEM TO BE SOLVED: To monitor a gain with high accuracy by digitally processing a level detection error produced by a pilot signal oscillator and a detector in a gain monitor circuit. SOLUTION: A level change due to a temperature change in a signal oscillator 1 generating a gain monitor pilot signal and a detector 5 outputting a DC voltage in proportion to a level of the pilot signal is stored in a temperature change compatible data storage section 71 and numeral data relating to an input pilot signal versus output voltage characteristic of the detector 5 are stored in advance into an input level versus output characteristic correspondence data storage section 72. A temperature change correspondence arithmetic section 91 at the input of the received signal reads a level change stored in the temperature change correspondence data storage section 71 is read to apply correction calculation to an output of the detector 5 corresponding to ambient temperature and an input level versus output characteristic correspondence arithmetic section 92 reads the numeral data stored in the input level versus output characteristic correspondence data storage section 72, and correction is applied to the output of the detector 5 to provide an output of a gain of an amplifier. |
